News Corp’s foundation US paper, the New York Post is bleeding badly. Its circulation dropped by a fifth in the six months to March, a loss of more than 114,000 copies in the six months, or 19,000 a month.

The weekday circulation average for the New York Post plunged to 558,140 copies for the six months ended March 30, according to the Audit Bureau of Circulations, which released figures overnight. (That’s about what the Herald Sun in Melbourne is selling daily).

The Post, edited by the controversial Australian Col Allan, blamed the crippling fall of 20.55% in six months on the doubling of its newsstand price to 50 cents. But that was in May of last year, so it couldn’t have been the major reason. Another possible reason is the now infamous cartoon inferring President Obama was chimpanzee which was published in February. That generated enormous publicity and controversy which forced Mr Murdoch and Mr Allan to apologise.

The Post’s decline was the worst performance of any of the country’s top daily papers and the news supports suggestions from US media analysts at investment bank UBS last week, that Murdoch’s traditional newspaper and TV businesses are facing greater challenges than just those posed by the recession.

The poor sales for the Post contrast with not only the performance at the Wall Street Journal (now worth half the $US5.6 billion Murdoch paid for it) but also doesn’t look at all good compared with the small gains in the UK for The Sun, The News Of The World and The Sunday Times in March.

The fall at the New York Post was almost three times the fall for the major daily newspapers of 7.1% in the six months to March, according to the latest figures from the American Audit Bureau of Circulations.

Of the top 25 newspapers in the United States, only The Wall Street Journal and Denver Post gained circulation during the period — the Denver Post through its absorption of the subscribers of the Rocky Mountain Times which was shut earlier this year.

The latest circulation figures for US newspapers for the October 2008-March 2009 period show the Wall Street Journal’s Monday to Friday edition was one of the few papers to lift sales in the period: up by less than 1% to 2.082 million copies, still behind Gannet’s USA Today which however suffered its biggest ever fall: down 7.5% to 2.113 million copies a day.

New York has emerged as the worst market for US papers. The Post’s rival, the Daily News suffered a sharp fall and the New York Times also lost ground, again.

The Post’s struggling Sunday edition dropped 11% to 357,168 copies. Weekday circulation at the rival New York Daily News dropped 14.3%, to 602,857 copies. Its Sunday paper fell 8.43% to 644,766 copies. The New York Times’ daily circulation fell 3.6 percent to 1,039,031.

The Audit Bureau of Circulations said average daily US newspaper circulation fell 7.1% in the October-March period from the same six-month span in 2007-2008. The latest figure represents data from 395 daily U.S. newspapers that reported in both the current and year-ago periods.

That was faster than the 4.6% drop recorded in the April-September period of 2008, and almost double the 3.6% fall recorded in same period of 2007-2008.

The Washington Post shed 1.16% to 665,383. The Los Angeles Times, owned by the bankrupt Tribune Co., saw its circulation dive 6.55% to 723,181. The Tribune’s flagship Chicago Tribune lost 7.47% to 501,202 copies a day.

Overall Sunday circulation fell 5.4% in the latest October-March period.

The New York Times continues to be the top newspaper on Sunday — when USA Today and The Wall Street Journal do not publish — though circulation dropped 1.7 percent to 1,451,233. The Los Angeles Times remains second, with a decline of 7.5 percent to 1,019,388.

Two newspapers in the top 25 posted Sunday increases, but both gains were less than 1%. Sunday circulation rose to 516,562 at The Arizona Republic and to 415,815 at the St. Louis Post-Dispatch.

Five of the top 25 Sunday publications posted double-digit declines, the biggest being the 19% slump at the Newark Star-Ledger. The New Jersey publication, owned Advance Publications Inc., was nearly closed before nearly 40% of its newsroom staff agreed to depart in a buyout wave.

And in the US magazine industry, Condé Nast has closed its two year old business magazine, Portfolio, after spending around $100 million on its launch and losses.

The magazine failed to gain enough readers and advertisers to compete against Forbes, BusinessWeek and Fortune. The magazine had a circulation of 415,000, not enough to compete with its rivals. Last October the magazine went from publishing monthly to 10 issues a year and its website portfolio.com cut staff. Now it’s gone, another victim of the great media implosion caused by the internet, the credit crunch and the recession.